Method and apparatus for translating or transmitting sound waves



455-618 AU 233 EX FIPBIOS XR 117189999 imw " y 2, .1929. T. w. CASE 1.718.999

IETHOD AND APPARATUS FOR TRANSLATING 0R TRANSIITTING SOUND IAVES Filed 001;. 7, 1922 PI [3. I.

If 4H Patented July 2, 1929.

UNITED STATES 1,718,999 PATENT OFFICE.

THEODORE WARD CASE, OF AUBURN, NEW YORK, ASSIGNOB TO CASE RESEARCH LABORATORY INCORPORATED, OF AUBURN, NEW YORK, A. CORPORATION OF NEW YORK.

I ETHOP APPARATUS FOR TBANSLA'IINGOB TRANSMITTING SOUND WAVES.

Application filed October 1, 1922. Serial No. 593,110.

This invention relates to a certain new and novel method and apparatus for translating or transmitting sound waves.

Attempts have been made to impress voice variations upon an electric are, but so far as I .am aware, no one has been able to produce an effective apparatus of that character, for the reason that the are is of such variable intensity and the temperature of the gases is so changeable, that it has been impossible to maintain a constant stability essential to commercial I translation or transmission. For that reason reprod uction, even at short distances, has been irregular, inaccurate and uncertain.

The essentials of my invention are, therefore, the combination with a source of light of high intensity, constant value and of the proper form and size for the purpose at hand, of means for varying such light in accordance with variations in sound waves, as for instance, the im ression of sound waves upon pm; of the com ustible fluids entering into the Another object-relates to the combination with an apparatus such as that referred to in the former paragraph of a photographic film upon which the variations in sound waves as translated in waves of light may be photograph or reproduced.

My invention is, therefore, adapted for many uses, and other objects relate to the details of form, construction and arrangement and its combination with various devices, all as will more fully appear from the following description, taken in connection with the ac companying drawings, in which Figure 1 is a diagrammatic illustration of an apparatus of my invention.

Figure 2 is a diagrammatic illustration of' a varied form of my invention embodying amplifying means.

Figure 3 is a diagrammatic illustration of trode 38- is connected to the filament a further embodiment of my invention. 0

Generally speaking, the apparatus of F gure 1 embodies a burner --1- upon which -voice variations may be impressed. Such burner may be enclosed in a suitable housing -2 embodying a reflector -3 for directmg the'light waves or rays in the manner desired, and this housing ma be closed at 1ts front end by a transparent p ate -4-of glass or the like.

For the purpose of receiving and translating'suchhght waves intosignals or sound waves, various apparatus may be used the one shown in Figure 1 consisting of a cel 5- embodying a light reactive materia or resistance of some character thafiaries m accor ance with the intensity of the light rays to which it is subjected. Such cell may be positioned in front of a reflector -6- concentrating the rays upon the cell. This cell 1s connected in circuit and forms a portion of the circuit which includes a battery 7 and a translating device, such as the telephone receivers -'-8.

The operation of this apparatus will be understood. l he variations in the flame produced at the burner --1-- will cause similar variations in the resistance of the cell --5, thereby varying the current flowing in the circuit containing the battery -7- and the receivers -8- so that said current will pulsate in the circuit at a frequency determined by the variations in the flame at the burner, thereby reproducing the sound waves impressed upon the burner.

Aperhaps preferred embodiment of 111 1;; I

ce ymgap paratus is disclosed in Figure 2', m iT'hic-Tatherm cell -35, includinrr a light reactive material positioned-near the path (TI the thermo-electric current and which varies its electron emission in substantial accordance with the intensity of the light rays to which it is exposed all as described in my 35 co-pending application Serial No. 523,603 filed Dec. 19, 1921. The'light reactive material should be adjacent the thermo electric current and may, as illustrated, be coated on a portion of the inner surface of the vacuum bulb. The cell 35- is connected in circult across the filament --10-- and the grid --1 1-- of the audion --9-, such'circuit including preferably a variable source of potential --12--. The filament 36 may be com nected to the grid -11 while plate or elec- 10- of the audion.

The filament 10 is connected in circuit with the plate 13- such circuit including a bat- 10o 't'ery, and if desired, a suitable'translatmg detion is effected by including in the circuit between the filament -10- and plate --13- the primary -14- of a transformer, the secondary 39'of which is connected across the. filament -15 and grid -16 of a second audion 17, the plate of which is connceted to the filament across battery --18- and a translating device, such as the telephone receiver -19. 7

By this construction of apparatus, a material am plifieation of pulsating currentot the device of Figure 1 and various stages or audion steps may be utilized in a device of this character.

The essentially novel arrangement is not, however, restricted to any particular circuits or any particular steps of amplification. An important portion of my invention resides in the transmitting or sending apparatus alone, and this apparatus includes the burner 1- which is of a peculiar construction, particularly when combined with a means for varying the flame of said burner in accordance with sound waves. This transmitting apparatus of my invention, so far as I am aware, produces for the first time a satisfactory flame of high intensity and constant value,

rendering the apparatus capable of effecting sensitive results when utilized in connection with a receiving or translating apparatus.

This sending apparatus comprises an acetylene burner -20 suitably connected to an acetylene tank 21 as by a flexible conduit 2- which may be provided with a suitable valve --40- for controlling the'flow of the combustible fluid. The conduit 22-- preferably has a branch 23- terminating in an enlarged preferably cone-shaped part 2l' constituting a mouth piece closed at its end by a diaphragm of suitable material. Any suitable diaphragm may be utilized, and I have used one formed of prepared paper tightly st-retched across the mouthpiece and secured in position in any Sound waves striking the diaphragm vary the pressure of the.fluid in the conduit 22- and thereby vary the intensity of the flame produced in the burner. I am, therefore, enabled to vary-the flame in accordance with articulate sound waves.

It is found that the ordinary acetylene flame is of little value for the purpose of this invention, and that an oxy-acetylene flame when the oxygen is introduced in the conduit --22-- is likewise of little practical value. I have, however, discovered that a flame of the desired h' h intensity and constant value'can be pro need by introducing oxygen directly into the acetylene flame.

Preferably, this is effected by directing two upwardly inclined streams of oxygen toward each other from opposite sides of the acetylene burner. and fixed nozzles --24 and 25--- are indicated for this purpose, and may be connected b a single conduit -26- to a tank 27 a apted to contain oxygen under pressure. The conduit 26- may contain a suitable valve -28- for controlling such communication.

By this burner a flame of substantially constant value and high intensity, and of the desired shape, spread and size may be produced,'and such a flame is peculiarly adapted for the translation and transmission of sound waves by reason of its high intensity and constant value.

In Figure 3 I have diagrannnatieally illustrated a modified form of burner as assembled with a photographing means for photographing variations in the burner flame produced by variations in articulate sound waves, altho the burner of Fig. 1 may be utilized and is in itself suflicient. This burner in addition to -the mouthpiece -24 and diaphragm with the usual and ordinary means for movin g the film across the aperture through which the light waves are admitted after passing through the double convex or concentrating lens -30- to the fihn space.-

By this apparatus there may be produced upon a film a photograph of the varying flame at the burner, which photograph may, in connection with a source of light and a translating apparatus embodying a light reactive cell, be utilized for reproducing the articulate sound waves which originally efl'ected the variations in the photographed flame.

It will be obvious that this sound transmitting and translating apparatus is capable of use in many and various assemblages and for many and various purposes, and I do not desire to limit myself to any particular independent translation or to any particular receiving apparatu I claim:

v '1. In an apparatus of the class described, a primary burner a source of combustible fluid under pressure having means of communication with the burner, means adapted to be operated by sound waves for varying the pressure of the fluid as supplied to the burner, a source of oxygen under pressure and means :for directing a stream of oxygen into a flame at the burner.

2. In an apparatus of the class described, via burner, means for supplying combustible fluid to the burner, means for varying the pressure of the fluid supplied to the burner in accordance with sound waves, a source of oxygen under pressure and means for directing a stream of oxygen into a flame at the burner.

3. A light wave transmitting apparatus comprising a burner including tubes for discharge of acetylene gas and oxygen gas, means for supplying said gases to their respective tubes, and means for varying the pressure of one of said gases in accordance with sound waves.

4. The method of varying a flame in aceordance with sound waves comprising producing a. flame by ignition of a combustible gas and varying the pressure of the gas supplied to said flame in accordance with sound waves, and introducing a second gas under pressure into said flame.

5. The method of varying a flame in accordance with sound waves comprising producing a flame by ignition of a combustible gas and varying the pressure of the gas supplied to said flame in accordance with sound Waves, introducing a second gas under prestions for oxygen and combustible gas. and

an acoustic diaphragm in contact with the combustible gas supply adjacent the burner whereby the visible length of the flame may be modulated by sound waves, and photographing upon a film the flame as varied.

In witness whereof I have hereunto set my handthis 291 h day of Septembcr1922.

THEODORE WILLARD CASE. 

